Most minimally invasive surgical procedures performed in the GI tract or other internal body cavities are accomplished with the aid of an endoscope. A typical endoscope has an illumination channel and an imaging channel both of which are made of a bundle of optical fibers. The illumination channel is coupled to a light source to illuminate an internal body cavity of a patient and the imaging channel transmits an image created by a lens at the distal end of the scope to a connected camera unit or display device. Most endoscopes also have a working channel through which an elongated treatment/surgical device may be passed. The treatment device usually has a handle or control at its proximal end that is manipulated by a physician to perform some surgical procedure.
While endoscopes are a proven technology, most are generally costly to manufacture. In addition, the optical fibers in the endoscope are subject to breakage during handling or sterilization procedures and are costly to repair. In order to limit breakage of the optical fibers, most endoscopes are relatively stiff. Such stiffness is usually achieved by making the working channel relatively small compared to the diameter of the scope. However, a small working channel limits the size of the medical device that can be inserted into the channel. Alternatively, if the working channel is made larger, the thickness of the endoscope is increased, thereby reducing the number of locations to which the scope can be routed.
Given these shortcomings, there is a need for an endoscope that does not rely on optical fibers for transmitting light into or images out of a body cavity. In addition, the endoscope should be able to be made with a relatively small diameter without unduly narrowing the size of the working channel.